This invention relates to indicia bearing elastomeric articles and a process for applying indicia to elastomeric articles.
Manufacturers of elastomeric articles, such as tires, belts and hoses, have a need to apply indicia to such articles for purposes of identification, advertisement and inventory control. For example, in the manufacture of power transmission belts such as V-belts and banded belts used in cars and other equipment, it is common for a manufacturer to apply labels indicating a company""s name, trademark, model number, date of manufacture and the like. To be beneficial, the labels need to remain intact despite the rigors of a harsh environment, e.g., an automotive engine compartment, and the indicia should be visible throughout the useful life of the belt.
A common way of labeling elastomeric articles has been by use of transfer release material. Release material of plastic film or paper is printed with indicia capable of transfer. The printed release material is typically used to apply the indicia to the elastomeric article during its manufacture and then is removed and discarded. For example, in, the manufacture of V-belts or banded belts, the release material is applied to a molding drum upon which various curable elastomer layers and reinforcing materials are sequentially wrapped. A jacket is placed over the wrapped article and the article is vulcanized. During vulcanization, the indicia are transferred from the inner surface of the release material to an adjacent elastomer layer. After the vulcanization process is completed, the release material is peeled away from the vulcanized belt leaving indicia on the outer surface of the just formed elastomeric article. However, the indicia applied in this manner then reside in a depression on the surface which is formed by the release material being present during molding. In the case of V-belts for automotive use, such irregularities on the surface of the elastomeric article generate unwanted noise when the belts are engaged with pulleys or idler rolls associated with various auxiliary equipment of the automobile engine compartments. In addition, the indicia applied in this manner reside on the outer surface of the elastomeric article and are unprotected from wear, heat, oils and harsh solvents common to the automotive environment.
The present invention provides an indicia bearing elastomeric article having a smooth outer surface. The article includes an elastomer layer having an outer and inner surface and a polymer film having an outer and inner surface, the polymer film having indicia on one of its surfaces. The inner surface of the polymer film is bonded to the outer surface of the elastomer layer so that the polymer film is flush with the outer surface of the elastomer layer making smooth the outer surface of the elastomeric article. In a preferred embodiment, polymer film is clear and the indicia is present on the inner surface of the polymer film and the polymer film serves as a protective covering for the indicia sandwiched between the polymer film and the elastomer layer, the indicia being visible through the protective covering.
The invention further provides for a process for forming an indicia bearing elastomeric article having a smooth outer surface. The process involves forming a polymer film having an outer and inner surface and applying indicia to one of the surfaces of the polymer film. The polymer film with indicia is applied to the outer surface of an elastormer layer and the film and the elastomer layer are pressed under conditions such that the film is bonded to and flush with the outer surface of the elastomer layer thereby making smooth the outer surface of the elastomeric article.